In this June 8, 2019 photo, US soldiers participate in a military tactical demonstration during a ceremony to commemorate the 75th anniversary of the Eighth US Army at Camp Humphreys in Pyeongtaek, South Korea. (JUNG YEON-JE / AFP)

SEOUL - South Korea on Tuesday criticized the US military’s decision to place thousands of Korean workers on unpaid leave this week, after the two allies failed to sign a new cost-sharing agreement.

S. Korea and the US are embroiled in a dispute dating back almost two years over how much each should pay to support the roughly 28,500 US troops stationed in S. Korea

South Korea and the United States are embroiled in a dispute dating back almost two years over how much each should pay to support the roughly 28,500 US troops stationed in South Korea, a legacy of the 1950-53 Korean War that ended in an armistice, rather than a peace treaty.

With no new pact months after the last agreement expired at the end of 2019, 4,000 to 5,000 of the nearly 9,000 South Koreans employed by the US military command will be placed on unpaid leave starting on Wednesday. US officials have said they will cover the payroll for any workers deemed essential.

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South Korean negotiator Jeong Eun-bo said South Korea regrets the move and that the United States had not agreed to proposals that would have prevented the furloughs while a new deal is hammered out.

“The decision by the US side to implement the unpaid leave for our workers as planned does not properly reflect the situation of the negotiations and we think this is regrettable,” Jeong told a briefing in Seoul.

“We urge the US to take measures to ensure the workers subject to the furlough scheme can swiftly return to work.”

The move comes as South Korea and the US military there battle outbreaks of the coronavirus, which has placed an economic strain on many residents.

United States Forces Korea (USFK) did not immediately respond to a request for comment. US officials have previously said that a separate deal to address the workers would have undermined efforts to reach an overall agreement.

Washington had demanded up to US$5 billion a year, more than five times the US$870 million that Seoul agreed to pay last year under a one-year deal, though US officials said they have “compromised” on the numbers.

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Jeong said that the two countries had “substantially narrowed” their differences and were making the utmost effort to sign a new agreement soon.

“We expect an agreement to be finalised soon,” he said.